Chapter 4: CellsChapter 4: Cells

Presented by Yellow Honors Biology Students

Presented by Yellow Honors Biology Students

The NucleusThe Nucleus

Section 4.4Section 4.4

NucleolusNucleolus

The nucleolus is where protein and RNA molecules are being constructed

Protein and RNA are subunits from which ribosomes are built and pass through the pores of the nuclear envelopes and reach the cytoplasm.

Ribosomes form at times of protein synthesis in the cytoplasm.

The nucleolus is where protein and RNA molecules are being constructed

Protein and RNA are subunits from which ribosomes are built and pass through the pores of the nuclear envelopes and reach the cytoplasm.

Ribosomes form at times of protein synthesis in the cytoplasm.

Nuclear EnvelopeNuclear Envelope

Two outer membranes surrounding the nucleus are called the nuclear envelope

DNA is anchored to envelope which keeps it organized

Lipid bilayers (the envelope) keeps out and control the flow of water soluble substances in and out of nucleus

Pores let in small molecules

Two outer membranes surrounding the nucleus are called the nuclear envelope

DNA is anchored to envelope which keeps it organized

Lipid bilayers (the envelope) keeps out and control the flow of water soluble substances in and out of nucleus

Pores let in small molecules

ChromosomesChromosomes

Chromosomes, which are defined as DNA molecules and their associated proteins, are found in the nucleus. Chromatin is known as the cells collection of DNA.

They have two forms; when the cell is not dividing, chromosomes appear as thin strands inside the nucleus. When the cell is dividing, the chromosome condenses into a double helix structure.

Chromosomes, which are defined as DNA molecules and their associated proteins, are found in the nucleus. Chromatin is known as the cells collection of DNA.

They have two forms; when the cell is not dividing, chromosomes appear as thin strands inside the nucleus. When the cell is dividing, the chromosome condenses into a double helix structure.

Section 4.5: The Cytomembrane System

Section 4.5: The Cytomembrane System

By Andrew Lindquist, Nobska Goodhue, Anna Bortnick, and Danny Flannigan

The Cytomembrane System is a series of organelles in which lipids are assembled and new polypeptide chains are

modified into final proteins. These products are shortened and shipped to their final destinations.

By Andrew Lindquist, Nobska Goodhue, Anna Bortnick, and Danny Flannigan

The Cytomembrane System is a series of organelles in which lipids are assembled and new polypeptide chains are

modified into final proteins. These products are shortened and shipped to their final destinations.

Endoplasmic ReticulumEndoplasmic Reticulum Functions of the Cytomembrane begin in the

endoplasmic reticulum (ER) In animal cells, the ER is continuous with the nuclear

envelope, and extends through the cytoplasm. Rough ER are typically observed as being arranged into

flattened sacs with many ribosomes attached. These ribosomes synthesize all new polypeptide chains. Once these chains are in the rough ER, enzymes may

attach oligosaccharides and other side chains to them, and these final proteins are secreted by many cells.

The smooth ER is free of ribosomes and curves through the cytoplasm, where most lipids are assembled.

Functions of the Cytomembrane begin in the endoplasmic reticulum (ER)

In animal cells, the ER is continuous with the nuclear envelope, and extends through the cytoplasm.

Rough ER are typically observed as being arranged into flattened sacs with many ribosomes attached.

These ribosomes synthesize all new polypeptide chains. Once these chains are in the rough ER, enzymes may

attach oligosaccharides and other side chains to them, and these final proteins are secreted by many cells.

The smooth ER is free of ribosomes and curves through the cytoplasm, where most lipids are assembled.

Golgi BodiesGolgi Bodies

Located in the cytoplasm, in eukaryotic animal cells

Golgi bodies are where enzymes put finishing touches on proteins and lipids for usage in the body

Finished proteins and lipids are packaged inside vesicles to ship to specific locations

Golgi bodies are composed of a series of flat, membrane-bound sacs

Vesicles form as sections of the membrane of the top sac break away into the cytoplasm

Located in the cytoplasm, in eukaryotic animal cells

Golgi bodies are where enzymes put finishing touches on proteins and lipids for usage in the body

Finished proteins and lipids are packaged inside vesicles to ship to specific locations

Golgi bodies are composed of a series of flat, membrane-bound sacs

Vesicles form as sections of the membrane of the top sac break away into the cytoplasm

Variety of VesiclesVariety of Vesicles

Vesicles are tiny, membrane sacs that move through the cytoplasm or take up positions in it

Lysosome are organelles of intracellular digestion and buds from the Golgo membrans of animal cells and certain fungal cells they contain diverse enzymes that speed the breakdown of proteins, complex carbohydrates, nucleic acids, and some lipids

Peroxisomes- tiny sac of enzymes that break down fatty acids and amino acids

Hydrogen peroxide, a potentially harmful product, forms during the reactions, helps break down alcohol

Vesicles are tiny, membrane sacs that move through the cytoplasm or take up positions in it

Lysosome are organelles of intracellular digestion and buds from the Golgo membrans of animal cells and certain fungal cells they contain diverse enzymes that speed the breakdown of proteins, complex carbohydrates, nucleic acids, and some lipids

Peroxisomes- tiny sac of enzymes that break down fatty acids and amino acids

Hydrogen peroxide, a potentially harmful product, forms during the reactions, helps break down alcohol

MitochondriaMitochondria

The barista of Eukaryotic cellsCreate ATP molecules (coffee), which are energy carrying nucleotidesMitochondria are located in the cytoplasm of a eukaryotic cell

The barista of Eukaryotic cellsCreate ATP molecules (coffee), which are energy carrying nucleotidesMitochondria are located in the cytoplasm of a eukaryotic cell

StructureStructure

2 compartments:1. outer membrane-->holds Hydrogen Ions

and controls the flow of energy

2. inner membrane-->folds on itself, creating the cristae

-->energy releasing reactions happen here

2 compartments:1. outer membrane-->holds Hydrogen Ions

and controls the flow of energy

2. inner membrane-->folds on itself, creating the cristae

-->energy releasing reactions happen here

FunctionFunction

Mitochondria break down organic compounds into carbon dioxide and water

They also form ATP molecules-->these are energy carrying nucleotides

Energy demanding cells have more mitochondria than those that do not need as much energy

They are the power house of eukaryotic cells Mitochondria require oxygen in order to function

Mitochondria break down organic compounds into carbon dioxide and water

They also form ATP molecules-->these are energy carrying nucleotides

Energy demanding cells have more mitochondria than those that do not need as much energy

They are the power house of eukaryotic cells Mitochondria require oxygen in order to function

Chapter 4.9By Diva, Olivia, and Timmy

Chapter 4.9By Diva, Olivia, and Timmy

The Structural Basis of Cell Motility

The Structural Basis of Cell Motility

Mechanisms of Cell Movements

Mechanisms of Cell Movements

Microfilaments, microtubules, or both take part in most aspects of mobility through three mechanisms

1. Length of a microtubule or microfilament can grow or diminish by the controlled assemble or disassembly of its subunits

2. Parallel rows of microfilaments or microtubules actively slide in specific directions

3. Microtubules or microfilaments shunt organelles or parts of the cytoplasm from one location to another

Pseudopods: temporary lobe-like protrusions from the body inside each lobe, microfilaments

Microfilaments, microtubules, or both take part in most aspects of mobility through three mechanisms

1. Length of a microtubule or microfilament can grow or diminish by the controlled assemble or disassembly of its subunits

2. Parallel rows of microfilaments or microtubules actively slide in specific directions

3. Microtubules or microfilaments shunt organelles or parts of the cytoplasm from one location to another

Pseudopods: temporary lobe-like protrusions from the body inside each lobe, microfilaments

Flagella and CiliaFlagella and Cilia

Flagellum and Cilia: structures for cell mobility

Have a ring of nine pairs or microtubules and a central pair

System of spokes and links stabilize the array

Centriole: barrel shaped structure that is one type of microtubule producing center

Basal body: refers to the location of the centriole

Flagella - longer and less profuse, sperm use the flagella as a tail to move

Cilia - stir air and fluids

Flagellum and Cilia: structures for cell mobility

Have a ring of nine pairs or microtubules and a central pair

System of spokes and links stabilize the array

Centriole: barrel shaped structure that is one type of microtubule producing center

Basal body: refers to the location of the centriole

Flagella - longer and less profuse, sperm use the flagella as a tail to move

Cilia - stir air and fluids

Flagella, Cilia and the Basal Body

Centriole

Eukaryotic Cell WallsEukaryotic Cell Walls

-The cell wall is a structural component, which wraps entirely around the plasma membrane.-Not only does it offer support physically to the cell owner, but it also protects it. -The wall is porous so that water and solutes can move to and from the membrane easily.-The primary wall consists glue-like secretions (polysaccharides, glycoproteins, and cellulose) which combine together to form the wall. This wall is thin and plyable.-Deposits on the primary wall’s inner surface combine to form a rigid, secondary wall, which reinforces cell shape.

-The cell wall is a structural component, which wraps entirely around the plasma membrane.-Not only does it offer support physically to the cell owner, but it also protects it. -The wall is porous so that water and solutes can move to and from the membrane easily.-The primary wall consists glue-like secretions (polysaccharides, glycoproteins, and cellulose) which combine together to form the wall. This wall is thin and plyable.-Deposits on the primary wall’s inner surface combine to form a rigid, secondary wall, which reinforces cell shape.

Matrixes Between Animal Cells

Matrixes Between Animal Cells

Animal cells don’t have cell walls. Therefore… Matrixes are composed of cell secretions and

materials from surroundings. These are the ‘walls’

Cartilage is made up of scattered cells, this forms collagen fibers in a ‘ground substance’ of modified polysaccharides

An extensive matrix yields a wide separation of cells

Animal cells don’t have cell walls. Therefore… Matrixes are composed of cell secretions and

materials from surroundings. These are the ‘walls’

Cartilage is made up of scattered cells, this forms collagen fibers in a ‘ground substance’ of modified polysaccharides

An extensive matrix yields a wide separation of cells

Cell-to-Cell JunctionsCell-to-Cell Junctions The only contact a cell has with the outside world is

through its plasma membrane In plant cells tiny channels connect adjacent cell’s

cytoplasm In animal cells there are three junctions; Tight

junctions, adhering junctions, and gap junctions Tight junctions link cells in the epithelial tissue, they

prevent water soluble substances from leaking through Adhering junctions join cells in organs subjected to

stretching Gap junctions link the cytoplasm of neighboring cells

allowing for a quick transfer of signals and substances

The only contact a cell has with the outside world is through its plasma membrane

In plant cells tiny channels connect adjacent cell’s cytoplasm

In animal cells there are three junctions; Tight junctions, adhering junctions, and gap junctions Tight junctions link cells in the epithelial tissue, they

prevent water soluble substances from leaking through Adhering junctions join cells in organs subjected to

stretching Gap junctions link the cytoplasm of neighboring cells

allowing for a quick transfer of signals and substances